Use contact cement to attach velcro strip to canoe. Barge brand is best. Most Ace or True Value hardware stores stock.
Notes from Ozone Production Manager:
Barge cement is a dry to dry contact cement, it’s not intuitive. There are many videos on Youtube on how to glue things together with contact cement.
Most important is for both surfaces to be clean & dry, from salt, dirt, and sand. Wash thoroughly with soap & water (citrus cleaner is best and will not damage canoe), let dry (foam will take about 24 hrs to dry well). Scuffing up the surface lightly may help a bit too. Otherwise, apply as directed on the package of Barge Cement.